My Two Cents
I am one of those people that was born to follow some kind of system. I started in high school (I won't tell you how many years ago that was, but it was a LOT!) I used Daytimer, Franklin Covey, you name it. And they all "worked".
And that's exactly what strikes me about your question: you ask "will it work"?
NO system works--YOU work. I think it's more a matter of what feels comfortable to you, natural--what suits your work style.
And I TOTALLY know what you mean about big promises and a lot of hype. That's one thing I think is very interesting about the GTD way--most of the overwhelming enthusiasm comes from those of us that are using it and loving it. I find the company itself to be much lower key in their approach--taking the consultative approach. Anything else would have turned me off years ago.
So I love the GTD world and have loved it for over 10+ years. I can't even imagine doing things differently without some parts of GTD remaining. But the only way to find out is to give it a shot. And take the feedback you get from the naysayers with a grain of salt. So many of those seem to me not to really even understand GTD, from what I've seen. I think it's interesting that the "anti-GTD" people are even bothering to read and post on a GTD forum, unless there is some motive other than to share tips and information other than using GTD.
I am the Party